Reading now what you said that the rears should be separated by as much space as the are different back from the listening area. Thats a much different spacing than the degrees of separation that I got.

With the current degrees of separation, that places the rears about 12'6" apart (ctc), with only 5' 2" from listening wall to rear wall.

There is 4.5 ft behind. there is a half wall at that point with pillars on each side about 3.0 ft in from the wall.The halfwall is 7.5 ft long. I will be sitting 4.5 ft in front on this wall. Behind this wall is a 3 ft walkway.From the front of the room my seat is 13 ft. I am 11 ft from the from of my L/C/R .I allowed 2 ft in the front from the speakers and tv.

Ok, I guess 7.2 just wasn't sure if there was that much of a distance to warrant and extra $600.I am mounting the side rears 6 ft from the floor and 95* off the sides. Given the room dimension I will be 6'9" to each side wall. mY rears I have calcualted to be 4'6" and 110*. I think, the paper work is upstairs. that puts them 3'6" from the side walls. OOPs I guess the room is 17.5' with a 3' walkway

Mark, no specific distance, just that the side surrounds should be distinguishable from the back surrounds by putting them directly to the side while the back surrounds should clearly be coming from a rear rather than side angle. What you describe still sounds okay.